Improvement in electric fuses



1m. SMITH. ELECTRIC-FUSE.

Patented Feb. 15,1876.

Engg a.

AIl.

H. Juntos-SMITH, ou Bo ummm/smentire Specification .forming p artoi,Letters ,Patent No. 173.68m, dated F .February-3, 1876.

T0 alL/whom-itma/y concern:

.Be it Iknown that I, H. JULIU'S SMITH, of Besten, in the county ot'Suffolk and State of Massachusetts, have in vented certain nenT andnseful'f Impro\-'ements in-Electrieal Fuses, of .whichfth'e following isa specification :l Thisinvention` relates to certainjmprovef mentsinfrietional .electric fuses,"it s;object be:` 'ing'.to'produce a fuse' ofsulicien t ,.0011.11tivity tb carry the electric eurrenteasily through'.-the v charge, whereby all tendeneyL-ofthecurrent to leaye the-wiresand takethfe'groundcirouit. Will-,be obyiated, and a current ot'suiiicientntensityjtransmitted .through the.ifus ,e} gto' ignite achargeof -any kind of,explosiveorliihninate, an'Lfurtber, 'tof eheapen'theconstruction of ehe-ruse." 'by iii-e; eminnyment- :efnnteriorfiauuless' expensive eonilu'tils ne? @Nearly-.fillsnlated, wh 'clitnexincreased' conductiyiity v of niyimproyement .enables me to employ.

My invention consists, trst,in the combina `tion','-witii theconducting-wires, betweentheir terinnalswithinthe fuse, ofasheet of.go1d,t silver, or other suitable foil, for the `purpose of conveyingthe current through the charge, ns hereinafter more fully set forthsecond, in` the combination, with the casing, of an insu` lating-b1ockof wood or other inateriahgrooveil or slotted on opposite sides,tormingrecesses for the reception ofthe conduetingwires, and a supportfor vthe foil which connects tneirter- -minals, .substantially nshereinafter set forth; third, in the combination, with the casing andinsulating-block, of an intermediate insulating-casing, to preventcontact between thev wires and casing, substantially as hereinafterdescribed; fourth, in the combination, with the insulating-block, ot'the conducting-wires, bent or .crimped to prevcntthcir withdrawal fromtheir recesses, or the turning or shifting offthe same. so as tol throwtheir ends oli' the connecting-sheet of foil, as incre fully hereinafterset forth; tit'th, in combination withI the. fuse and explosiveeomponnd,the conncct-ingsnoei, of foil and iron .condnoting-wires,.insulated withcotton or othercheap insulating niatexials, substantially as hereinafterdescribed,

'ln the drawing; Figure 1 represents an elevation 'of my improved fuse;Fig. 2, a view siren, MAssAGHUsEfr-frs.

-ELEcTRlc Fuses.l V

ebruary 15, 1876; application filed partly in elevation and partly insection; Fig.

3 represents. an elevation and a. section of the insulating-block,and-Fig.` 4 represents a per- 'spectii'e Y`vieiviof;y thefjblock andconductingwirosf-ff .L y

filhedetterA'represents .,a'casingfoi'. metal or other '1 suitable.`material, provided .with 'a fshoulder aboutgnidway between 'its-twoends. l. The casing is'lpreferafblyvmadeof such diamefterand4 lengththat .an ordinary blasting-cap ivillI-t-nea'tly upon the 4forvirardendet' the .-Asame, 'the' extent to which it can be forceddown uponCsaid tube .being limited bythe shoulder tolprevent danger. The letter!)representsan insalatingfblock, fot wood or other; insulating material, Aextending labout half-way. ,in 'to-l :the 'casing`,"'anlfrecessed orSlGtted'iong l udinnjlly on opposite .sides for Vthe receptionioi theconi dnoting-:i'rires l) l). Said conducting-vriresarc constructed,preferably, of.irony or'other'fcheap v'metalfaiid insulated by" meansof= .cqtto1 r. or other inexpensive textile material, 'reinen .may '-fbevcoated with any resinous v's'.il)s. i;;i,i.ce vto, iu-

crease its insulating properties and-'freuder it Waterfprootl The condnctin g'- wires -are`,7'1'iret' era-bly,` bent orcriinpetl, as shown .inEig. 3, to prcveirtfthe.shifting or turning. oif thesame in therecesses.` The-letter E represents the con;

necting-stri p or sheet of gold, silver',"orotl1er foil,l which' jiys,cemented orotherwisesecured.- on the end of the insulating-block, thetermi-' nals ot' lthefwires O'being bent-down over ,opposite edges ofthesanle, in Fig. 4. 1n orderto .pre rent from passing. from thc Wiresto th an intermediate insulating-casing, suitable material, iskinterposed b two. The forward end ofthe casing A con- .'stitutes thecharge-cham ber, and maybe lilled with an e casing,

closed.

The fuse, as thus constructed', offers] no resistanceto the passa rent,and therefore it is n the most iiertect conduct terialsfwhich are exfuses too costly and, further,

ors and insulating' mafor many bythe actionot' thecnijrentupon asclearly .indicated vent 'the electric cury explosive or fulminate, alterwhich the open end' may be cemented or otherwise ittle or' ge ot theelectriccurnnecessary to employ pensive, 'and render. the

ordinary prposes the foil, the charge is invariably fired, as the foilis heated and lvolatilized bythe passage of the,

curreni,=creating a. heat of sufficient int `ensit5r and duration toignite the least-'sensitive ex-- plosives..- Bythis means I canconstruct the fuse with a single charge-chamber and. av'od thenecessity. o f'exnpl'oying a series of cham- `bers for'l charges ofdifferent degrees of4 sensitiveness, asin the fuses heretoforeconstructed;

and, further, by dispensing with the extremely' sensitive end dangerousfulminates heretofcre' `found necessary, I- produce a fuse that isat-ftended with'nodanger whatever. f

What I claim, and desire to secure by Let-v ters Patent,' is'- 1. Incombination with the conducting-Wires of effictional electric fuse, aconnecting-sheet of gold, silver, orlothersnitable Foil interposedtial'lyas,descrihed. j 2. lIn -combineti'o'n with the casing A, the.insulatingfblock, grooved -cr y recessedl longibetween'the terminalsofsaid Wiles,4 substenvthe subscribing witnesses. t.

H. JULIUS SMITH,

tudilnall-y for lthereception .ot the connectingwires, and forming asupport for the foil, substantially as described.

3; The combination of the casingffinternie- 'diete insulating-casing,and insulating-block, containing the wires and foil, snbstnntiallyas 4,'In conibination -with the recessed insulatin `1r-block, the. wires bentor crimped sshosvn, for the purpose described. i Y

15. In combination fwith.. the fuse containing the explosivecompound,;the connecting sheet of fOiL-fand the iron conducting-wires,insulated l by means o f cotton or other cheap insulating material,substantially as described.

In testimony that. I claim' the foregoing I have hereunto set my hand`rin the presence'of Witnessem JAMES L. NoRRIs, Jos. L. Cocinas.

